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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Agromine associant plantes hyperaccumulatrice de nickel et légumineuse, comme service écosystémique des sols ultramafiques / Assessment of ecosystem services rendered by agromining of nickeliferous soils : testing the association of leguminous and hyperaccumulator plants

Saad, Ramez 03 November 2017 (has links)
L’application de l’agromine à des zones ultramafiques délaissées constitue un enjeu majeur à la vue des surfaces potentiellement valorisables. Par contre, les sols ultramafiques sont particuliers avec de fortes concentrations en métaux et une quasi absence de matière organique. Malgré tout, la mise en place de l’agromine a déjà donné de bons résultats, couplée avec l’application d’herbicides et une fertilisation minérale. Notre défi a été de développer une agromine durable par la mise en place d’agro-écosystèmes basés sur l’introduction d’une légumineuse en association avec une plante hyperaccumulatrice et la suppression de tout intrant chimique. Nos résultats ont confirmé clairement que l'introduction d'une légumineuse dans l’agromine a amélioré la production de biomasse de Alyssum murale et les rendements de nickel par rapport à sa monoculture fertilisée et non fertilisée. Nos travaux ont également montré que l'insertion d'une légumineuse dans l’agromine permet d’améliorer la structure du sol avec des agrégats plus stables. De plus, de meilleures teneurs en carbone, azote et en matière organique ont été détectées. L’ensemble de ces éléments conduit ainsi à une amélioration globale de la structure du sol, de sa fertilité et de son biofonctionnement. Corrélativement, nos résultats ont mis en évidence les effets positifs de ces nouvelles pratiques, à la fois sur la taille, la diversité et les acitivités liées aux cycles biogéochimiques des communautés bactériennes. D’un point de vue écononique, l’introduction de la légumineuse dans l’agromine implique un gain financier et de temps du fait de la réduction de l'application d’engrais et de produits phytosanitaires. Enfin, tous ces avantages conduisent à une réhabilitation des sols ultramafiques avec une restauration de leurs qualités physique, chimique et biologique, tout en permettant à ces sols particuliers d’offrir plusieurs services écosystémiques / The application of agromining to abandoned ultramafic areas is a major challenge in the presence of potentially recoverable areas. Howerver, ultramafic soils are particular in terms of their fertility with high concentrations of metals and a near absence of organic matter. Nevertheless, this challenge was partly met by the application of chemical fertilizers and herbicides. Our challenge, through this PhD, was to develop a sustainable agro-ecosystem based on the introduction of a legume in association with the hyperaccumulating plant and then the reduction of any chemical input. Our results clearly confirmed that the introduction of a legume into these new cropping systems improved both the biomass production of Alyssum murale and the Ni yields in comparison to the fertilized and non-fertilized monoculture. Our work has also shown that the insertion of a legume into agromining cropping systems improves the structure of the soil due to stable and larger aggregates. In addition, higher levels of carbon and nitrogen and higher concentrations of organic matter were detected. These results led to an overall improvement of the soil structure, its fertility and its biofunctioning. Our results showed positive effects of these new cropping systems, both on the size of the bacterial communities and on the microbial enzymes involved in the soil biogeochemical cycles. In addition, the structure and diversity of bacterial communities were modified with the insertion of the legume, compared to the monoculture. Economically, the introduction of legume into cropping systems dedicated to Ni agromining involves a gain of money and time due to reduced application of mineral fertilizers as well as products of phytosanitary. Finally, all these benefits lead to the rehabilitation of ultramafic soils with the restoration of their physical, chemical and biological qualities while allowing these particular soils to offer many ecosystem services
332

Porovnání dvou lokalit s rozdílnou intenzitou zemědělského využití z hlediska poskytovaných ekosystémových služeb / Comparison of two areas with different level of intensity of agricultural exploitation as concerns the ecosystem services

KUNT, Lukáš January 2015 (has links)
The aim of this thesis is to evaluate two localities with different intensity of agricultural use in terms of ecosystem services provided by nature habitats. In connection with the evaluation of the sites is in the works documented incidence size seminatural habitats, natural calculated value of the studied area using Biotope Vaulation Method (Seják et al., 2003) Application MapoMat developed by the Agency for Nature Conservation and Landscape. The value of ecosystem services is determined through expert analysis by replacement cost. There were differences in the value of ecosystem services important habitats between conventional and organic farming at localities 1 and 4. Natural habitat value conventionally used the site has a 2.53 milKč compared to the organic farming locality where the value was estimated at 194.6 milKč, In this context that the value of ecosystem services locations 1 shows a value of 4438.96 milesCZKyear-1 compared to location 4, calling shows a value of 7905.01 milesCZKyear-1. On this basis, were statistically significant differences in both localities in terms of the frequency of diversity factors examined specimens of ground beetles are examined diversity index P <0001.
333

Zhodnocení přírodní hodnoty a ekosystémových služeb přírodě blízkých biotopů v intenzivně využívané zemědělské krajině / Evaluation of the natural value and ecosystem services of natural biotops in the intensively managed agricultural landscape

HAVEL, Jaroslav January 2015 (has links)
My thesis is focused on valuation methods intensively used agricultural landscapes according to the importance of near-natural habitats in terms of their natural values and ecosystem services. This is done at four sites using pitfall traps, where there was a catch beetles (Carabidae). To evaluate the data I used indicators such as the Shannon index serenity. Procedures for calculating the ecological value of the area and the ecosystem services provided I processed according to the proposed method Seják et al., (2010). Rating I performed by BVM (,, habitat valuation methods "). Replacement cost method I used for the calculation of ecosystem services.
334

"The Living Landscape" projekt - česká perspektiva / "The Living Landscape" Project - Czech Perspective

VEBER, Tomáš January 2017 (has links)
This thesis deals with the phenomenon of ecological recovery of ecotone backyard, a specific phenomenon in rural areas of the Czech Republic, focusing on the one hand synchronously, partly diachronic. Theoretically, based on the scientific literature discusses the topic first as a phenomenon in itself, then focuses on the description of the possibilities that may be related to the maintenance or revitalization of the ecotone recover or regain, both in the dimension of eco-environmentalist, and in the dimension of socio-ethnographic.
335

Ekosystemtjänster i svenska kommuner : Implementering av begreppet i dagligt arbete och beslutsfattande / Ecosystem services in Swedish municipalities : Implementation of the concept in daily work and decision making

Nilsson, Hanna January 2018 (has links)
Idag lever människan, som följd av bland annat en ökad befolkningsmängd och allt mer ohållbara konsumtionsmönster, långt över jordens kapacitet. Detta leder till degradering av jordens ekosystem och den biologiska mångfalden vilket i sin tur påverkar dess förmåga att leverera ekosystemtjänster som människan är direkt beroende av. Begreppet ekosystemtjänster är framtaget för att öka medvetenheten hos människor om varför naturen är viktig ur ett mänskligt perspektiv och för att ge den en större plats vid beslutsfattande. Kommunerna spelar en viktig roll när det kommer till att arbeta med ekosystemtjänster då de står för stora delar av den fysiska planeringen. Syftet med denna studie var att genom en enkät undersöka hur ett urval av Sveriges kommuner arbetar med ekosystemtjänster. Studien visar att svenska kommuner fortfarande befinner sig i en inledningsfas när det gäller att arbeta med ekosystemtjänster, begreppet är etablerat i teorin men det finns stora svårigheter med att implementera det i praktiken. En vilja finns men även en upplevd brist på kunskap samt bristande lagstiftning och stöd ovanifrån vilket sätter käppar i hjulet. Det finns många möjligheter och utmaningar för kommunerna framöver när det kommer till att, med hjälp av ekosystemtjänster, arbeta mot ett hållbarare samhälle. / Today, partly because of an increased population and unsustainable consumption patterns, human kind lives way over the world's capacity. This leads to degradation of the earth's ecosystems and biodiversity, which affects its ability to deliver ecosystem services on which humans are directly dependent. The concept of ecosystem services has been developed to raise awareness about why nature is important from a human perspective and give it a larger place in decision making. At a local level, the municipalities play an important role when it comes to working with ecosystem services as they control much of the spatial planning. The purpose of this study was, through a survey, to investigate how a selection of Swedish municipalities works with ecosystem services. The study shows that Swedish municipalities are still in an initial phase of ecosystem services work, where the concept is established in theory, but there are major difficulties implementing it in practice. There is a general will to work with the concept, but also a lack of knowledge as well as legislation and support from above. There are many opportunities and challenges for the municipalities in the future when it comes to working, with ecosystem services, towards a more sustainable society.
336

Dopad úpravy území bývalého tankodromu na jeho ekosystémové služby / Impact of the adjustment of the area of former tank training area on its ecosystem services

PAČKA, Jiří January 2013 (has links)
The ecological value and the value of ecosystem services of the former military area in Čtyři Dvory in České Budějovice was evaluated in this thesis. The expert method of BVM (?Biotope Valuation Method?) and the Replacement Cost method (cost of technological alternative to ecosystem function) according to Seják et al. (2003, 2010) were applied. Four ecosystem services were evaluated: climatic service (evapotranspiration), little water cycle, oxygen production, and the support of biodiversity. For comparison, the sale price of the area and the ?recreation? value calculated by the contingent valuation (CV) method were also evaluated. The estimated sale price was 837 million CZK, which was by twelve-times higher than the ecological value estimated by the BVM method. Most of the area (57 %) was formed by the biotop XK4 ? pioneer shrub vegetation of atropogenic noncultivated areas with 13 points per m2. The most valuable biotop was V2.2 ? periodic waters with 44 points per m2, which formed 1.5 % of the examined area. The estimated value of ecosystem services was 1 372 millions CZK per year. The realization of all the planned construction projects on the examined area would lead to the depression of the ecological value according to the BVM method by 19.5 millions CZK and the depression of the value of the formerly mentioned four ecosystem services by 459 millions CZK.
337

Nucleação como precursora na restauração de áreas degradadas e no fornecimento de serviços ambientais em áreas verdes urbanas

Junior, Francisco Pimenta 22 August 2017 (has links)
Submitted by Marcio Emanuel Paixão Santos (marcio.santos@ucsal.br) on 2018-06-21T21:27:01Z No. of bitstreams: 1 DISSERTACAOFRANCISCOPIMENTAJUNIOR.pdf: 1939347 bytes, checksum: ba72edebc4b2afc4a468623041f340c5 (MD5) / Approved for entry into archive by Linda Bulhosa (linda.gomes@ucsal.br) on 2018-06-25T13:23:30Z (GMT) No. of bitstreams: 1 DISSERTACAOFRANCISCOPIMENTAJUNIOR.pdf: 1939347 bytes, checksum: ba72edebc4b2afc4a468623041f340c5 (MD5) / Made available in DSpace on 2018-06-25T13:23:30Z (GMT). No. of bitstreams: 1 DISSERTACAOFRANCISCOPIMENTAJUNIOR.pdf: 1939347 bytes, checksum: ba72edebc4b2afc4a468623041f340c5 (MD5) Previous issue date: 2017-08-22 / Esta dissertação trata do uso de técnicas nucleadoras na recuperação de áreas degradadas em áreas urbanas fim de promover serviços ambientais, diante da necessidade da conservação e do uso de técnicas inovadoras na recuperação. A expansão urbana contribui para o aumento gradativo das áreas degradadas, contribuindo para a fragmentação de ecossistemas e perdas em biodiversidade. A não gestão de áreas degradadas contribui para incremento de áreas improdutivas, a formação de processos erosivos, empobrecimento do solo e comprometimento de áreas adjacentes às áreas degradadas. Existem modelos de recuperação dessas áreas, que se baseiam em especial no plantio de mudas, com o foco mais dendrológico e que adota práticas de silvicultura, no entanto vem se discutindo o uso de modelos de restauração que buscam o retorno da estabilidade e integridade biológica, sendo esta técnica denominada de nucleação, baseada em processos ecológicos. Também é importante proporcionar meios de subsistência e serviços ambientais das terras degradadas, identificando possíveis medidas que acentue a recuperação e os serviços ambientais prestados. Com esse enfoque, o presente trabalho tem como objetivo verificar o potencial da nucleação no fornecimento de serviços ambientais e na recuperação de áreas degradadas em áreas urbanas. O trabalho é composto por três capítulos que tratam dos serviços ambientais, de métodos iniciais de restauração e de uma proposta de protocolo de avaliação de serviços ambientais na recuperação de áreas degradadas em áreas urbanas, respectivamente. No trabalho verifica-se que a nucleação possui um potencial muito expressivo no fornecimento de serviços ambientais, ainda que através de práticas simples como a transposição de solo e serapilheira, no entanto os planos e programas de recuperação devem estar alinhados com a vocação e a necessidade da área degradada e do contexto do seu entorno principalmente se tratando de áreas urbanas. / This dissertation deals with the use of nucleating techniques in the recovery of degraded areas in urban conservation units in order to promote environmental services, in view of the need for conservation and the use of innovative recovery techniques. Urban expansion contributes to the gradual increase of degraded areas, contributing to the fragmentation of ecosystems and losses in biodiversity. The non-management of degraded areas contributes to the increase of unproductive areas, the formation of erosive processes, the impoverishment of the soil and the compromise of areas adjacent to degraded areas. There are models of recovery of these areas, which are based in particular on planting of seedlings, with a more dendrological focus and adopting silvicultural practices, however the use of restoration models that seek the return of stability and biological integrity, Being this technique called nucleation, based on ecological processes. It is also important to provide livelihoods and environmental services for degraded lands, identifying possible measures that enhance recovery and environmental services provided. With this focus, the present work aims to verify the potential of nucleation in the provision of environmental services and in the recovery of degraded areas in urban conservation units. The work consists of three chapters dealing with environmental services, initial restoration methods and a proposal for a protocol for the evaluation of environmental services in the recovery of degraded areas in urban areas, respectively. In the work, it is verified that nucleation has a very expressive potential in the provision of environmental services, although through simple practices such as soil and litter transposition, however recovery plans and programs must be in line with vocation and need of the degraded area and of the context of its environment, especially in urban conservation units.
338

Understanding the relationship between urban best management practices and ecosystem services

McDonough, Kelsey R. January 1900 (has links)
Master of Science / Biological & Agricultural Engineering / Stacy L. Hutchinson / Increasing attentiveness to climate change and the dependence of human life on natural resources has spurred awareness about the detrimental impacts of human activity on the environment. Ecosystem services, or the benefits that humans derive from ecosystems, have changed more in the past 50 years than in any other comparable period in human history (Carpenter et al., 2009).The dilemma of managing the trade-off between immediate human needs and maintaining the ability of the Earth to provide ecosystem services is considered to be one of the largest challenges of this century (Foley et al., 2005). The ecosystem service concept aims maximize the provision of services across an entire ecosystem to achieve overall ecosystem health through land management, policy, and economic decisions. The intent of this research was to improve such decisions by increasing the understanding about the relationship between urban best management practices and freshwater provision, erosion regulation, and flood regulation ecosystem services. Fifty-six land management scenarios with varying densities of BMP application were simulated using the Stormwater Management Model (SWMM). The ecosystem services resulting from these land management scenarios were quantified using indices developed by Logsdon and Chaubey (2013). Results demonstrate that the application of bioretention cells improve both freshwater provision and erosion regulation services immediately downstream from the implementation site, and an increase in erosion regulation services was observed at the greater watershed scale. There was no change in the provision of freshwater, erosion regulation, or flood regulation services observed by the application of green roofs or rain barrels at either scale of analysis.
339

Planning for Urban Ecosystem Services: Generating Actionable Knowledge for Reducing Environmental Inequities in Santiago de Chile

January 2017 (has links)
abstract: Cities are hubs for economic and social development, but they are increasingly becoming hotspots of environmental problems and socio-economic inequalities. Because cities result from complex interactions among ecological, social and economic factors, environmental problems and socio-economic inequalities are often spatially interconnected, generating emergent environmental inequity issues due to the unfair distribution of environmental quality among socioeconomic groups. Since urban environmental quality is tightly related to the capacity of urban landscapes to provide ecosystem services, optimizing the allocation of ecosystem services within cities is a main goal for moving towards more equitable and sustainable cities. Nevertheless, we often lack the empirical data and specific methods for planning urban landscapes to optimize the provision of ecosystem services. Therefore, the development of knowledge and methods to optimize the provision of ecosystem services is essential for tackling urban environmental problems, reducing environmental inequities, and promoting sustainable cities. The main goal of this dissertation is to generate actionable knowledge for helping decision-makers to optimize the allocation of urban vegetation for reducing environmental inequities through the provision of ecosystem services. The research uses the city of Santiago de Chile as a case study from a Latin-American city. To achieve this goal, I framed my dissertation in four linked research chapters, each of them providing methodological approaches to help link environmental inequity problems with the development of urban planning interventions promoting an equitable provision of urban ecosystem services. These chapters are specifically aimed at providing actionable knowledge for: (1) Identifying the level, distribution, and spatial scales at which environmental inequities are more relevant; (2) Identifying the areas and administrative units where environmental inequities interventions should be prioritized; (3) Identifying optimal areas to allocate vegetation for increasing the provision of urban ecosystem services; (4) Evaluating the role that planned urban vegetation may have in the long-term provision of ecosystem services by natural remnants within the urban landscape. Thus, this dissertation contributes to urban sustainability science by proposing methods and frameworks to address urban environmental inequities through the provision of ecosystem services, but it also provides place-based information that can be readily used for planning urban vegetation in Santiago. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2017
340

Avaliação da influência dos pagamentos por serviços ambientais sobre a estrutura da paisagem / Evaluation of the influence of payments for environmental services on the landscape structure

Maridelia Rios Gonzaga 03 October 2016 (has links)
Esta pesquisa contempla a questão dos pagamentos por serviços ambientais (PSA), instrumento cada vez mais utilizado no Brasil e no mundo para a conservação e recuperação de recursos hídricos por meio da proteção e restauração florestal. As iniciativas de PSA baseiam-se em incentivos aos fornecedores de serviços ecossistêmicos condicionados à oferta de tais serviços. O sucesso na aplicação desse instrumento está fortemente atrelado a procedimentos de monitoramento que demostrem os efeitos das ações adotadas no âmbito dos esquemas de PSA sobre os serviços ecossistêmicos. Entretanto, a literatura aponta que procedimentos de monitoramento nem sempre são adotados e, quando o são, por vezes não abarcam indicadores importantes para a avaliação do sucesso dos esquemas. Sendo assim, o objetivo desse estudo é contribuir para o aprimoramento do uso do instrumento Pagamento por Serviços Ambientais para a conservação dos recursos hídricos, incluindo a perspectiva da ecologia da paisagem, com vistas à sustentabilidade dos ecossistemas florestais protegidos e/ou restaurados. Para tal, foram realizados três estudos de caso em três municípios brasileiros distintos. Dois destes casos, localizados nos municípios de Extrema (MG) e Rio Claro (RJ), foram esquemas de PSA nos quais proprietários rurais receberam incentivos financeiros para promover a conservação e/ou recuperação florestal. O terceiro caso estudado, localizado no município de Bonito (MS), diz respeito a um projeto institucional baseado nos instrumentos de comando e controle (C&C) sem adoção de PSA. Foram utilizadas imagens orbitais de alta resolução e ferramentas de geoprocessamento que possibilitaram o cálculo dos índices métricos de paisagem em cada uma das áreas de estudo e da mudança em tais índices em um intervalo de tempo de aproximadamente sete anos. Além disso, a título de comparação, os mesmos índices foram calculados para locais próximos às áreas de estudo e com características ambientais semelhantes (denominadas \"áreas vizinhas de referência\"), considerando o mesmo intervalo de tempo. Os resultados mostram que tanto nas áreas objeto de esquemas de PSA como na maioria das demais áreas analisadas (com exceção da área vizinha de referência do município de Bonito) ocorreram pequenos aumentos na área de floresta e redução da média do isolamento entre os fragmentos florestais. No entanto, apenas na área objeto de PSA em Extrema houve salto positivo significativo na cobertura florestal e na média do isolamento (distâncias euclidianas) no intervalo de tempo estudado. / This research addresses the issue of Payments for Environmental Services (PES), a mechanism increasingly used in Brazil and in the world for the conservation and recovery of water resources through the protection and forest restoration. PES initiatives are based on incentives to providers of ecosystem services conditioned to the offer of such services. The successful implementation of this instrument is strongly linked to monitoring procedures that show the effects of the adopted actions on ecosystem services. However, the literature indicates that monitoring procedures are not always adopted, but when adopted, they often do not cover important indicators for evaluating the success of the schemes. Thus, the aim of this study is to contribute to the improvement of the instrument, PES, for the conservation of water resources, including the perspective of landscape ecology in the monitoring actions, aiming the sustainability of protected and/or restored forest ecosystems in object areas of PES schemes. For this, three case studies were conducted in three different Brazilian municipalities. Two of these cases, conducted in Extrema, MG, and Rio Claro, RJ, were PES schemes, in which farmers received financial incentives to promote forest conservation and/or recovery. The third case study, conducted in Bonito, MS, refers to an institutional project based on command and control (CAC) instruments, without adopting PSA. High-resolution satellite images and geoprocessing tools were used and allowed the calculation of landscape metric indices in each study area, in addition to changes in these indexes in a period of about seven years. Furthermore, for comparison purposes, those indexes were calculated for locations near the study areas with similar environmental characteristics (called \"neighboring reference areas\"), considering the same time interval. The results show that in the object areas of PES schemes and in most other analyzed areas (with the exception of the neighboring reference area in Bonito), there were small increases in forest area and reduction in the average isolation between forest fragments. However, only in the area of PES in Extrema there was a significant positive balance in forest cover and in the average isolation (euclidean distance) in the studied time interval.

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